In recent decades, global climate change and ecological problems caused by the greenhouse effect have become a serious threat. Methane gas is an important greenhouse gas, and its temperature-increasing efficiency is 21 times that of carbon dioxide. According to statistics, the overall contribution of methane gas to the global greenhouse effect is up to 22%, and methane gas is a greenhouse gas which has the fastest annual increase rate.
As the population and economic and living levels continuously increase, the production amount of household refuse also increases rapidly. Refuse landfill is an important technical means for treating household refuse in a few countries (particularly developing countries). In a long-term anaerobic environment, household refuse in landfill fields will generate a large amount of landfill gas with methane as a main component. Indeed, household refuse landfill fields have also become one of the important sources which emit methane gas. It is reported that the amount of methane gas emitted from refuse landfill fields is 20-70 Tg·a−1, and the proportion accounting for the total amount of global methane gas emission has been increased to 12%-20%. Therefore, the reduction of methane gas emission in household refuse landfill fields is an important task for every country in the world to control and reduce global greenhouse gas emission.
At present, landfill gas collection and utilization systems are generally provided in large household refuse landfill fields, and they may effectively utilize the landfill gas released from household refuse landfill fields and reduce the emission of methane gas. However, the landfill gas collection and utilization system is complex for installation and has high manufacture cost. Since the gas generation intensity of methane gas is low for middle and small household refuse landfill fields, the collection system has low efficiency and it is difficult to ensure normal operation of the landfill gas utilization system. Therefore, the landfill gas collection and utilization systems are not suitable for the middle and small household refuse landfill fields. How to effectively control the emission of landfill gas in the middle and small refuse landfill fields (without landfill gas collection and utilization systems) is a commonly concerned challenge at present in the field of environmental protection.